office-gobmx/compilerplugins/clang/redundantpointerops.cxx
Noel Grandin 57b185a972 loplugin:redundantpointerops, look for ".get()->"
Change-Id: I396864b4dea3341b78634cb74555cfb78f1aea25
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/86551
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>
2020-01-11 11:59:46 +01:00

199 lines
6.9 KiB
C++

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
* This file is part of the LibreOffice project.
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*/
#ifndef LO_CLANG_SHARED_PLUGINS
#include <cassert>
#include <string>
#include <iostream>
#include <fstream>
#include <set>
#include <clang/AST/CXXInheritance.h>
#include "check.hxx"
#include "compat.hxx"
#include "plugin.hxx"
/**
* Look for:
* (&x)->y
* which can be transformed to:
* x.y
* And
* &*x
* which can be:
* x
*
* @TODO
* (*x).y
* which can be:
* x->y
*/
namespace {
class RedundantPointerOps:
public loplugin::FilteringPlugin<RedundantPointerOps>
{
public:
explicit RedundantPointerOps(loplugin::InstantiationData const & data): FilteringPlugin(data) {}
virtual void run() override
{
if (preRun())
TraverseDecl(compiler.getASTContext().getTranslationUnitDecl());
}
bool VisitFunctionDecl(FunctionDecl const *);
bool VisitMemberExpr(MemberExpr const *);
bool VisitUnaryOperator(UnaryOperator const *);
private:
bool isSmartPointerType(const Expr* e);
};
bool RedundantPointerOps::VisitFunctionDecl(FunctionDecl const * functionDecl)
{
if (ignoreLocation(functionDecl))
return true;
// if (functionDecl->getIdentifier() && functionDecl->getName() == "function6b")
// functionDecl->dump();
return true;
}
bool RedundantPointerOps::VisitMemberExpr(MemberExpr const * memberExpr)
{
if (ignoreLocation(memberExpr))
return true;
if (compat::getBeginLoc(memberExpr).isMacroID())
return true;
auto base = memberExpr->getBase()->IgnoreParenImpCasts();
//parentStmt(parentStmt(memberExpr))->dump();
if (memberExpr->isArrow())
{
if (auto unaryOp = dyn_cast<UnaryOperator>(base))
{
if (unaryOp->getOpcode() == UO_AddrOf)
report(
DiagnosticsEngine::Warning,
"'&' followed by '->' operating on %0, rather use '.'",
compat::getBeginLoc(memberExpr))
<< memberExpr->getBase()->getType()->getPointeeType()
<< memberExpr->getSourceRange();
}
else if (auto operatorCallExpr = dyn_cast<CXXOperatorCallExpr>(base))
{
if (operatorCallExpr->getOperator() == OO_Amp)
report(
DiagnosticsEngine::Warning,
"'&' followed by '->' operating on %0, rather use '.'",
compat::getBeginLoc(memberExpr))
<< memberExpr->getBase()->getType()->getPointeeType()
<< memberExpr->getSourceRange();
}
else if (auto cxxMemberCallExpr = dyn_cast<CXXMemberCallExpr>(base))
{
auto methodDecl = cxxMemberCallExpr->getMethodDecl();
if (methodDecl->getIdentifier() && methodDecl->getName() == "get")
{
auto const e = cxxMemberCallExpr->getImplicitObjectArgument();
if (isSmartPointerType(e))
report(
DiagnosticsEngine::Warning,
"'get()' followed by '->' operating on %0, just use '->'",
compat::getBeginLoc(memberExpr))
<< e->IgnoreImpCasts()->getType().getLocalUnqualifiedType()
<< memberExpr->getSourceRange();
}
}
}
// else
// {
// if (auto unaryOp = dyn_cast<UnaryOperator>(base))
// {
// if (unaryOp->getOpcode() == UO_Deref)
// report(
// DiagnosticsEngine::Warning, "'*' followed by '.', rather use '->'",
// memberExpr->getLocStart())
// << memberExpr->getSourceRange();
//
// }
// }
return true;
}
bool RedundantPointerOps::VisitUnaryOperator(UnaryOperator const * unaryOperator)
{
if (ignoreLocation(unaryOperator))
return true;
if (compat::getBeginLoc(unaryOperator).isMacroID())
return true;
if (unaryOperator->getOpcode() != UO_Deref)
return true;
auto subExpr = unaryOperator->getSubExpr()->IgnoreParenImpCasts();
auto innerOp = dyn_cast<UnaryOperator>(subExpr);
if (innerOp && innerOp->getOpcode() == UO_AddrOf)
report(
DiagnosticsEngine::Warning, "'&' followed by '*' operating on %0, rather use '.'",
compat::getBeginLoc(unaryOperator))
<< innerOp->getSubExpr()->getType() << unaryOperator->getSourceRange();
if (auto cxxMemberCallExpr = dyn_cast<CXXMemberCallExpr>(subExpr))
{
auto methodDecl = cxxMemberCallExpr->getMethodDecl();
if (methodDecl->getIdentifier() && methodDecl->getName() == "get")
{
auto const e = cxxMemberCallExpr->getImplicitObjectArgument();
if (isSmartPointerType(e))
report(
DiagnosticsEngine::Warning,
"'*' followed by '.get()' operating on %0, just use '*'",
compat::getBeginLoc(unaryOperator))
<< e->IgnoreImpCasts()->getType().getLocalUnqualifiedType()
<< unaryOperator->getSourceRange();
}
}
return true;
}
bool RedundantPointerOps::isSmartPointerType(const Expr* e)
{
// First check the object type as written, in case the get member function is
// declared at a base class of std::unique_ptr or std::shared_ptr:
auto const t = e->IgnoreImpCasts()->getType();
auto const tc1 = loplugin::TypeCheck(t);
if (tc1.ClassOrStruct("unique_ptr").StdNamespace()
|| tc1.ClassOrStruct("shared_ptr").StdNamespace())
return true;
// Then check the object type coerced to the type of the get member function, in
// case the type-as-written is derived from one of these types (tools::SvRef is
// final, but the rest are not; but note that this will fail when the type-as-
// written is derived from std::unique_ptr or std::shared_ptr for which the get
// member function is declared at a base class):
auto const tc2 = loplugin::TypeCheck(e->getType());
if ((tc2.ClassOrStruct("unique_ptr").StdNamespace()
|| tc2.ClassOrStruct("shared_ptr").StdNamespace()
|| (tc2.Class("Reference").Namespace("uno").Namespace("star")
.Namespace("sun").Namespace("com").GlobalNamespace())
|| tc2.Class("Reference").Namespace("rtl").GlobalNamespace()
|| tc2.Class("SvRef").Namespace("tools").GlobalNamespace()))
{
return true;
}
return false;
}
loplugin::Plugin::Registration< RedundantPointerOps > redundantpointerops("redundantpointerops");
} // namespace
#endif // LO_CLANG_SHARED_PLUGINS
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */